John Smyth wrote: >Well, after Dave's posting I went through my CD collection and, (yikes!) >I found six suspect Hyperion CDs. ... Two are unquestionably bronzed, one >is questionable, and the remaining three are golden-colored, yet seemingly >ok. All were on the list of possible defectives. > >My question: If the three ok CD's haven't bronzed yet, will they ever? >(All have been sitting in close proximity to each other for @4-5 years.) >Is the rate of corrosion even, or do some CDs take longer than others to >corrode? We really don't have enough information to know. Presumably, if PDO released detailed reports of the chemistry and processes that lead to the defective acetate mixture, someone might be able to make some educated guesses. Also, we don't really know the extent of the problem even during the years in question (late 1989 to early 1991). Were all discs made during that time made with the same defective batch of acetate? Were various batches used, each with varying susceptibility to the acid used in the paper? Was the defect the result of low-quality ingredients, the wrong ingredients, some foreign contaminant, or some combination of these? What effect does the proximity of the booklet, or the types of dyes used, or other factors such as ambient temperature/humidity, have on the rate of bronzing? We don't have any idea, and these are just some of the issues I can think of that might effect the rate of bronzing. The criteria I used to determine whether to ask for a replacement was subjective. If the disc was showing even the slightest discoloration that appeared to be bronzing (not to be confused with the even amber tint many of these discs have naturally), I asked for a replacement. Further, if I knew I bought a disc that was on the list during the time of the defective pressings, or within a few years after that period, I asked for a replacement. This was facilitated because I track purchase date in my collection database. For instance, if I had a 1990 release on Hyperion that I knew I bought in 1991 or 1992, and it was on the list, I asked for a replacement. This happened in only a handful of cases as most discs in this category had already bronzed. It seems unnecessary, but a few private messages I've received have expressed some confusion I'd like to clear up. Just because a disc appears on the list DOES NOT mean it will eventually bronze. Neither Polygram nor any of the affected labels has issued a recall, to my knowledge, so there is every chance that there are still some defective discs out there on the shelves waiting to be bought. But depending on the popularity of a given release, the chance of picking up a disc that has been on the shelf for a decade is relatively small, I imagine. Bob Stumpf wrote: >Apparently the problem may be more extensive. Dave wrote that >"CDs manufactured before 1989 and after 1991 have not been reported as >suffering the same corrosion." I had a copy of DG 419-780, Bernstein >conducting Harris and Schuman, that bronzed. It was pressed in 1987 >according to the insert and there is no PDO anywhere I could find. A little perspective is in order I think. First, everyone must realize that manufacturing processes are not perfect. Though in an ideal world factories would produce products that were 100% defect-free, but in the real world all production lines are subject to failures, large and small. As I doubt any plant regularly does 100% inspection on the tens or hundreds of millions of CDs produced - and even 100% inspection is no guarantee a defective discs won't slip through - some defects will make it to the consumer. No technology can guarantee zero defects. This means that it's axiomatic that every single CD manufacturing plant in the world has produced and shipped defective discs. If PDO could screw up a lacquer formulation, then it's just about a certainty that others could reproduce their error, and this is just one of the things that might go wrong. I would never expect that bronzing is limited just to CDs produced by PDO in the UK. We already know that PDO in Germany, OPTI.ME.S. in Italy, as well as CDV in France, have produced CDs that are bronzing, for instance. What sets the PDO problem apart is both the extent of the defect, as well as their response. Apparently a large quantity of discs are produced that were defective in exactly the same way, and the defect can be traced directly to a known cause. I would not be at all surprised to find that over the coming decades a few more of the discs in my collection will "go bad" for one reason or another. This doesn't indicate to me that the problem is more extensive, just that nothing's perfect. Norman M. Schwartz responds to Robert Stump who writes that DG states: >>"As this particular recording is not available anymore, we cannot send >>you a new CD from our warehouse. So the enclosed CD is an advance copy >>(therefore without printed label) which got made for our internal use >>before the release." > >Could discs of this type be characteristic of DG's "Archives on Demand" >program for deleted catalog items? If so, shipping them without appropriate labels will probably kill the service before it gets off the ground. I can't imagine that this will fly with the consumer. What I suspect Bob got was from a pre-production run to verify the glass masters. What doesn't make sense, if this is the case, is why they'd still have those around and not production copies made later. Is Bob sure this is a CD, and not a CD-R or CD-RW? These latter two would look bluish green as they use a dye instead of an aluminum substrate. I also think that if this is indicative of a larger problem with some DG releases they will be eventually compelled to make another production run to provide replacements. As I consider this further, I wonder if classical labels, and the factories they use to press their CDs, have made a miscalculation with respect to the perception of quality in the classical CD world. Let me illustrate with an example. Most purchasers of pop CDs are not in it for the "long haul" as most classical buyers are. This is not to say that there aren't avid and extremely knowledgeable collectors of pop, jazz, etc., just that they constitute a smaller percentage of sales in their respective genres (with the possible exception of jazz, I admit). Most purchasers of a Hyperion CD, for example, are probably going to hang on to it for quite some time and know this going in. Further, it is more likely to be part of a "collection" that may be in use for decades. Contrast this with most purchasers of the latest N'Sync CD, who are predominantly teens and pre-teens. They are likely only looking for a few years of use before the disc gets misplaced or damaged, or they simply lose interest, whether they are conscious of the fact or not. Consequently, over the decades the labels/factories that have applied the same level of quality control to pop and classical CDs may find their replacement commitment to classical collectors to be rather more substantial, as a percentage of sales, than to pop collectors. Mitch Friedfeld wrote: >It would be a catastrophe if my copy of Mahler's Songs of Youth -- Hyperion >CDA66100 -- went bronze. Dame Janet Baker and Geoffrey Parsons are the >perfect team here. As far as I know, there is no other complete recording >of these early masterpieces. Zu Strassbourg auf der Schanz.... I know how Mitch feels. All of the Unicorn-Kanchana CDs that are bad in my collection are irreplaceable, unless you count getting lucky in a used CD store, and all of them are badly bronzed. They are no longer available from Unicorn (and they seem to barely be alive anyway), so if PDO was not being cooperative with replacements, I'd be out of luck. But with a Hyperion release, I think you can relax. Hyperion has been proactive in addressing this issue, and even if PDO disappeared tomorrow, I suspect Hyperion would honor their commitment to the customer and replace the discs themselves. As a follow-up to my previous post, I have now received a second shipment of replacement discs from PDO, which was sent the day after the first shipment. I'm waiting on a final batch of 28 CDs from them (they have sent over 100 so far), and I'll be all set. With this last shipment, PDO has requested that I return the bronzed CDs to them, and I will be doing so as soon as I receive all the replacements and spend a day in my CD room putting them away. Dave [log in to unmask] http://www.classical.net/